Insulating glass units (IGUs) are used in windows and doors to reduce heat loss from building interiors during cold weather. IGUs are typically formed by a spacer assembly sandwiched between glass lites. A spacer assembly has a frame structure extending peripherally about the insulating glass unit. A sealant material bonds the glass lites to the frame structure and a desiccant for absorbing atmospheric moisture within the unit, trapped between the lites. The margins or the glass lites are flush with or extend slightly outwardly from the spacer assembly. The sealant extends continuously about the frame structure periphery and its opposite sides so that the space within the IGUs is hermetic.
U.S. Pat. No. 5,361,476 to Leopold discloses a method and apparatus for making IGUs wherein a thin flat strip of sheet material is continuously formed into a channel shaped spacer frame having corner structures and end structures, the spacer thus formed is cut off, sealant and desiccant are applied and the assemblage is bent to form a spacer assembly.
U.S. Pat. No. 7,610,681 to Calcei et al. (hereinafter “the '681 Patent”) concerns spacer frame manufacturing equipment wherein a stock supply station includes a number of rotatable sheet stock coils, an indexing mechanism for positioning one of the coils, and an uncoiling mechanism. Multiple other processing stations act on the elongated strip of sheet stock uncoiled from the stock supply station. The disclosure of the '681 Patent is incorporated herein by reference.
U.S. Pat. No. 7,448,246 to Briese et al. (hereinafter “the 246 Patent”) concerns another spacer frame manufacturing system. As discussed in the '246 Patent, spacer frames depicted are initally formed as a continuous straight channel constructed from a thin ribon of stainless steel material e.g., 304 stainless steel having a thickness of 0.006-0.010 inches. As noted, other materials such as galvanized, tin plated steel, or aluminum can be used to construct the spacer frame. The disclosure of the '246 Patent to Briese et al. is also incorporated herein by reference. Typical thickness for these other materials range from 0.006 to 0.025 inches in thickness.